Railroad employees use a multipurpose tool (See U.S. Pat. No. 5,481,950) commonly referred to as a brakestick to operate handbrakes on railroad cars from the ground. The tool consists of a sliding or telescoping handle assembly, a locking mechanism to hold the sliding sections of the assembly in place and a specially designed hook for engaging the railroad car brake wheel. Use of the tool prevents injuries related to climbing on railroad cars to operate handbrake wheels as well as injuries resulting from operating the brake wheel itself. The tool enhances both safety and productivity.
The brakestick can experience significant tension when pulled on by the user to tighten or loosen brake wheels. The design of past and current locking systems of the brakestick have resulted in the inner rod of the brakestick handle breaking, the inner rod being pulled out of the outer tube, jamming of the locking mechanism, and the locking mechanism failing to securely hold the inner rod in place after the inner rod has been locked in the desired position.
The most popular locking system uses a mechanical device to grip lateral grooves cut into the inner rod. The grooves weaken the structural integrity of the inner rod which has resulted in the rod breaking when the brakestick is in use (See U.S. Pat. No. 6,182,539). Other locking systems use internal camlocks, spring loaded ball plungers, or other mechanical devices to secure the inner rod. Each of which have proven difficult to operate or inadequate to hold the inner rod in place.
Therefore a need exists for a novel telescoping handle assemblies. A further need exists for novel locking mechanism for telescoping handle assemblies for tools, such as which may be for use with a railroad car. There is also a need for novel telescoping handle assemblies having a simple and robust design that eliminates all the aforementioned problems that have been experienced with previous locking systems.